Some type of magnetic heads employ separate read and write modules in which ferrite is used as the pole pieces or substrate. The ferrite modules are mounted within a housing, which may be made of aluminum or another nonmagnetic material. A significant problem that is experienced with such head assemblies is that as a result of the differences of the coefficients of thermal expansion of the ferrite modules and housing materials, changes in ambient temperature cause dimensional fluctuations with resultant misalignment of the magnetic head parts, including the read and write transducing gaps. If the read and write modules comprise multi-track heads having a multiplicity of aligned transducing gaps, the problem is more critical.
One of the solutions that has been offered includes the matching of the ferrite material with the materials of the housing, so that the values of the thermal coefficients of expansion are similar or close. An optimum material for this purpose is titanium for use in a housing wherein ferrite modules are employed. However, titanium is very difficult to machine and relatively expensive. Other solutions that have been offered to solve this problem are complex and costly, and are not totally effective, especially for those multi-track heads that are made relatively small and have closely spaced transducing gaps.